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Failure about to happen?
14

Failure about to happen?

RE: Failure about to happen?

Is that in a location where you occasionally get several feet of snow, followed by steady rain?


RE: Failure about to happen?

Well, I'm not a structural guy but I know that doesn't look right...

RE: Failure about to happen?

Yikes.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Failure about to happen?

Any idea how that came to be? Was the roof raised? Rube Goldberg must have been involved.

RE: Failure about to happen?

How long has the building been there?
I just how that it isn't in an earthquake zone.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Failure about to happen?

Self cleaning feature. Hit the roof with a big hammer and whole thing vibrates like a tuning fork, dislodging all the dust. Patent Pending!

RE: Failure about to happen?

Looks like they cleaned-out the trash bin as they were putting the finishing touches on the roof supports. Whatever they found, they put to good use.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Failure about to happen?

The load's not 'that' high... and the flanges would nearly produce a fixed end condition with the web... as Ron will tell you, a good part of forensic engineering is determining why things stand up, when they really shouldn't.

Dik

RE: Failure about to happen?

In structures where crash energy management is required mechanical "fuses" are common.

But for a roof?

RE: Failure about to happen?

(OP)
One of our engineer's was out shopping with his wife this weekend and took that photo. I've asked him to find out where it was.
On an ethical view I suppose I should forward to the city building dept. and have them review.

The concern here is that the lower column has nothing laterally supporting it except for the web of that WF piece.

It may stand for 40 years but whoever did that should be made to do push ups or something.

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RE: Failure about to happen?

Nothing to add except shaking my head... and that piece of WF has a bolt pattern in the web.

Analog spoken here...

RE: Failure about to happen?

That might be worse than 20+ shim plates tack-welded together

RE: Failure about to happen?

Quote:

One of our engineer's was out shopping with his wife this weekend

Nothing good ever comes from going shopping.

RE: Failure about to happen?

Now we all know what a slender column is.

RE: Failure about to happen?

No one caught this before now?! Not the EOR? Not the building department? Not the inspector? Not the contractor?

Sigh....

RE: Failure about to happen?

That's a work of art! Do not take that beauty down.

RE: Failure about to happen?

I'm no structural engineer, but that column looks a little undernourished to me.

RE: Failure about to happen?

The question I have and I am not a structural guy is " Are there any more like that, or is that the only one? " .
B.E.

You are judged not by what you know, but by what you can do.

RE: Failure about to happen?

I was gently wondering if the bit of roof on the right was an extension, and they were expecting a LOT of lateral motion in the main roof due to say sun load. The plate would act as a leaf spring and tolerate that lateral motion. I've (well, a cluey CAD guy working for me) done something like that in the past on a smaller scale.

Cheers

Greg Locock


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RE: Failure about to happen?

That UC on the left looks a whole heap heavier than the truss on the right and is supported on what looks like a pretty flimsy piece of angle iron... That must be putting a pretty serious moment on the strut top and hence a decent lateral force on that piece of sheet steel.

It is a bit on a wonder as to why it hasn't actually bent and collapsed yet.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Failure about to happen?

Why the predrilled holes in the stub beam? Presumably for something to be attached. I'm more concerned about what's missing.

RE: Failure about to happen?

Looks like the ironworkers realizes mid-job their columns were a couple foot short and did some field engineering to correct it.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: Failure about to happen?

It looks so wrong but also so deliberate. Is the column below just clad or is it concrete, perhaps acting as a cantilever? Is it tapered or is that just the perspective?

RE: Failure about to happen?

Around 2001, one person was killed in a mall roof collapse in Sarnia ON. It was due to snow load, although total average accumulation on the roof was well within allowable. A combination of drifting and a significant step (basically an 8 foot transition in elevation) led to a very heavy drift pileup at one location. Thankfully (relatively) it happened before the mall opened, so there were no shoppers inside yet.

I can't be sure but I think that roof was better supported than this one appears to be. Actually the first thing in the photo that caught my attention was how flimsy the roof panels are, especially to the left of the slender column.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: Failure about to happen?

Quote (cooperDBM)

It looks so wrong but also so deliberate. Is the column below just clad or is it concrete, perhaps acting as a cantilever? Is it tapered or is that just the perspective?

All of the above?

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: Failure about to happen?

The important thing is if it all worked in Revit.

RE: Failure about to happen?

(OP)
OK - so he went back last night and took another photo of it from the other side.
There is a single stiffener on that opposite side which makes me feel a little better.
The load coming down from above is still eccentric to the "T" shaped piece of column (beam web plus stiffener) but at least there's something.

However, if the WF roof beam is fully loaded the eccentricity of the load might be too much.

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RE: Failure about to happen?

Any thoughts on the purpose of the 6 predrilled holes in the short beam section (shown in the original photo). For attachment of bracing?

RE: Failure about to happen?

As I was coming back from the store this AM, it dawned on me that some engineers will go through hoops to achieve a pinned connection.

Dik

RE: Failure about to happen?

It looks like someone decided to raise the height of the roof by a couple of feet AFTER all of the steel had been cut. That fabricated angle-iron segment looks like a filler piece to me.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Failure about to happen?

So I was curious and checked this like a stepped column. assuming 20' tall, and top 5' is equal to a WT4x15.5, bottom is an HSS8x8x3/8, the critical buckling load would be about 94 kips, or an allowable load of about 56 kips, neglecting eccentricity. that is a 30'x30' bay at 60 psf allowable.

RE: Failure about to happen?

Is it just the picture angle, or does it appear that there is a bow in the column (second photo) with the little chunk of "garbage" in the middle a bit to the right of the overall end-to-end centerline?

RE: Failure about to happen?

It would be funny if that was an unneeded pillar and instead of tearing the pillar down they connected it to just keep it upright.

------------------------------------------------------------------------------------------
If you can't explain it to a six year old, you don't understand it yourself.

RE: Failure about to happen?

(OP)
So drawing a straight line from bottom mid-point on column to top mid-point on column there is definitely some bow in it.


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RE: Failure about to happen?

Wow. Regardless of the numbers, would not seal.

I suspect the roof level needed to be changed because they needed new racking or it was a new tenant. They set jacking equipment under the beam ends, cut the beam, jacked it up, and did not want to put in the effort to cut out the beam segment that remained. Saved $2k - 5k in welding/testing a full penetration weld.

RE: Failure about to happen?

It just dawned on me, "Why would anyone do that?"... let alone an engineer review and accept that... really scarey, and if it goes, it will go catastrophically... no warning... 'bang' and it's down. Someone should notify the building department rather than just chat about it.

Dik

RE: Failure about to happen?

Quote (HamburgerHelper)

It would be funny if that was an unneeded pillar and instead of tearing the pillar down they connected it to just keep it upright.
That looks awfully structural to me. It's at a transition from a beam to a truss so there is definitely a bending moment on it. But, I'm not a structural guy.

Brad

It's all okay as long as it's okay.

RE: Failure about to happen?

The photo is a bit misleading; you can see that the topmost flange is twisted relative to the truss directly above it. The apparent bow is partly due to the fact that the hole in the top flange is not aligned with the stuff below it. If you were to extend the line to where the hole should be, that middle section wouldn't look as bowed.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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RE: Failure about to happen?

Why the holes? Presumably to impart strength - in the same way the perforations in bog roll do.

Taking tongue out of cheek now: How did that stiffener get there? Is there a type of rolled beam that comes with stiffeners like that scattered here and there along its length (how would you go about making such a product?) or is the presence of the stiffener evidence that somebody put real thought and effort into making a special fabrication?

A.

RE: Failure about to happen?

I think it is apparent that the building was extended, both horizontally and vertically. The short piece of WF which now forms part of the column was once a roof beam, part of a cantilever and drop in system. Probably very little if any involvement in the extension by a qualified engineer.

RE: Failure about to happen?

I'm guess that the original section spanned several columns in the original life of the building. Perhaps for a crane?

When converted to retail that was probably no longer architecturally acceptable, so just cut out the bits between columns.

But still, welding in that stiffener was probably more expensive than fabricating and installing a proper column shape.

RE: Failure about to happen?

(OP)
This was and is a retail building.
There is also another detail just beyond this one in the first photo I posted.

I believe that hokie66 is correct - the building was altered (vertically and horizontally) and they simply built the new structure up and then later came back and cut away the beam below, leaving the stub there to serve as a part of the vertical column.

This will be pushed to the local building dept. by me. I feel an obligation to at least raise the issue with them.

Just thought it was an appropriate "failure" for this forum.



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RE: Failure about to happen?

My eyes may be deceiving me, but that stiffened plate looks to be about the same height as the WF beam connected to the top of the column. Any chance they originally planned for Beam to sit atop the column. and that's how it ended up too short?

RE: Failure about to happen?

Moral of the story - got an issue, just add stiffener(s) till it looks like it might work.

Be interesting to see how the original designer justified that to themselves...

RE: Failure about to happen?

I think hokie66 and hot rod have it nailed.


If you take that stub extension piece and rotate it 90 degrees it more or less matches the end of the deep beam which presumably sat on the column post. That kind of explains why is has a set of holes drilled in it - it was originally on the end of the beam and intended to connect to another beam?

Now the Truss comes along and they want to support it on the top flange so need the column extended the height of the column - easy, let's just prop the beam, chop off the end section of the beam, weld on a teeny weeny angle bracket and use the cut off end as an extension piece....Oh and we'd better weld on a stiffener to stop the beam piece buckling - only one mind!

So the truss section is the horizontal extension.

Is it just me or does it look like the bottom of that stub extension piece is just resting on the top of the column? i.e. not bolted?

Still looks horrible.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Failure about to happen?

Probably (hopefully) welded.

RE: Failure about to happen?

This is a Walmart building extender... patent pending...

Mike McCann, PE, SE (WA)


RE: Failure about to happen?

I imagine the stiffener was always there. It is typical practice to provide stiffeners where a beam passes over a column.

RE: Failure about to happen?

True: Ominously, I don't see any bolts between the end of the truss (all the way up at the roof) and the flat plate on the final vertical part of the column. Only two empty drilled holes.

I suspect the earlier diagnosis is correct: The WF was intended to rest on the top of the column, but the field changed it to a bolted joint to the web of the WF. The rest was a cut-and-fit job to get the height right.

RE: Failure about to happen?

racookpe,
I think it would be standard practice to weld rather than bolt that truss girder to the supporting column.

The WF at the top was originally bolted to the lower WF, then the connection was changed when the roof was raised. Is that what you meant?

RE: Failure about to happen?

Yes.

RE: Failure about to happen?

8
(OP)
The local authority has been copied on these photos with an address. We'll see if anything comes to pass on it.

Here's the (redacted) text of my email to them:

As we discussed this afternoon, the attached photos are of a column configuration that one of my engineers saw in a local building.
The address is #################.

This is a “big box” retail building and I believe there are at least two columns with this condition.

Since I am a licensed SE in ######, seeing a detail like this where I believe that there may be a public safety issue compels me to bring this to the attention of either the building owner or you. I don’t know who is the owner so I am forwarding this concern to you to see if you believes that some notice or action is required.

I have not performed any calculations or analysis of this other than visual examination of the conditions.

Two of the photos (Bad Column Details 3 and close-up in 4) include a redline on the photo which shows a perceived slight bowing of the column arrangement such that bending in this configuration could be magnified by heavy roof snow loads and possibly lead to second order effects on the column.

It appears that this may have been a building with a lower existing roof frame that had a newer, higher roof system built using an upper column extension over the original roof beam. The new upper roof was framed in and the lower roof beams were cut off completely except for the portion of beam in line with the column.

From one photo there is a vertical plate stiffener on the web of the beam piece, but this is on one side only.

From my perspective, I would think that the appropriate action would be to have the building owner contact the original engineer, if available, to review this as-built condition and respond as to its capacity with respect to the Omaha Building Code provisions for roof dead load, snow, live, etc.

They could also hire another engineer as well to get an unbiased look at it. We, of course, would recuse ourselves from that effort.

It may result in a finding that the column is adequate but visually it is such an unusual configuration that we feel it best to have a closer look at it.

Please contact me if you have any questions.

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RE: Failure about to happen?

I'd caution about mentioning the bending (if it's not too late to edit). Cell phone cameras tend to have a minor fish-eye quality due to the tiny lens. This may be the source of the curvature (or may not).

Edit: Also, typo:

Quote (Letter)

so I am forwarding this concern to you to see if you believes that some notice or action is required.

Ian Riley, PE, SE
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries https://www.facebook.com/AmericanConcrete/

RE: Failure about to happen?

(OP)
Ian - Thanks for the comments.
My engineer who took the photos said the bend is clearly visible and the line I drew simply illustrates it.

My email to them is red flag - not meant as a technical proof of anything.

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RE: Failure about to happen?

Good call, JAE....appropriate approach to inform the AHJ

RE: Failure about to happen?

PS....how many hinges do you need in a column? lol

RE: Failure about to happen?

I honestly don't know if I would notice or be concerned by a feature like this anymore as I frequent many buildings that are on their n^th repurpose. Even in the various manufacturing plants I work in, seeing an extra beam or column hanging here or there overhead is a common site as its often cheaper/easier/etc to leave them in place than remove.

RE: Failure about to happen?

^ All well and good until someone "repurposes" without doing the appropriate checks that it's going to be okay afterward, and it isn't ...

RE: Failure about to happen?

We could say the same thing about breathing if the next guy's an idiot, can't live in a bubble forever and if there's no valid reason to spend extra time and money beyond appearance then its the owner's call. I'd wager the majority of homes in the US have old wiring and plumbing in the walls that's long since been disconnected and abandoned in place, same concept could be happening here.

RE: Failure about to happen?



Speaking of unusual remodeling. I spotted this at a bar this weekend with some friends. Building was probably built in the 30's and is a 1 story builing. But the remodel was probably done in the last 4-5 years. Beam was not continuous over the top of the... air condition vent. Column didnt appear appear to go through the air condition either. That gusset plate was probably about 1/4'' thick too.

RE: Failure about to happen?

As Jackson Brown put it "Everybody walks right by like they're safe or something
They don't know-"

RE: Failure about to happen?

A couple of 1/4" gusset plates can hold quite a bit...you'd probably find those 4 strips of steel together have nearly the capacity of the post...

...and it's Jackson Browne.

RE: Failure about to happen?

JAE:

The bend you see could have been there from the start as rhere are bearing stiffeners on only one side of the beam element from what I see.

Could have warped the Web during welding.

Mike McCann, PE, SE (WA)


RE: Failure about to happen?

When the truss reactions are different from the girder reactions, the unbalanced moment will put a lateral force and/or impose a displacement on the top of the odd spacer with holes and one web stiffener, subjecting it to eccentric loads. I smell a cascade failure, injuries and lawsuit.

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